libmagic is a software library used for determining the type of data within a file, usually by examining its contents rather than relying on its extension or metadata. It is commonly used by file managers, email clients, and other programs that need to identify the contents of a file.
The libmagic library is usually accessed through a command-line tool called file, which provides a human-readable description of the file type based on the output of libmagic. For example, file example.pdf might output “PDF document, version 1.4” if libmagic determines that the file is a PDF document.
libmagic is often used in Unix-like operating systems, including Linux and macOS. It was originally developed by Ian Darwin and is now maintained as part of the file command project. The library is available under a BSD-style license and is widely used in open-source software.
In summary, libmagic is a library used for identifying the type of data within a file by examining its contents, and it is commonly accessed through the file command-line tool.